CLN/TST: Pyarrow CSV engine

[arw2019]

This is a master tracker for the more cosmetic follow-ups to #38370: styling, testing, etc.

• BUG: import_optional_dependency doesn't check version for submodules #38888 correctly check version for optional dependency submodule imports (to handle import pyarrow.csv)

[lithomas1]

Can't edit the OP, but wanted to add

• Convert all pyarrow_skip markers to pyarrow_xfail. This was previously disabled due to timeouts.

[mroeschke]

I think we have a dedicated issue for #38889 (comment) and our minimum version of pyarrow should guarantee pyarrow.csv to be available so closing